:root {
    --bg-primary: #0a0a0a;
    --bg-secondary: #1a1a1a;
    --bg-card: #2a2a2a;
    --text-primary: #ffffff;
    --text-secondary: #b0b0b0;
    --text-muted: #808080;
    --accent-blue: #4a9eff;
    --accent-green: #4ade80;
    --accent-purple: #a855f7;
    --accent-orange: #fb923c;
    --border-color: #404040;
    --shadow-light: rgba(255, 255, 255, 0.1);
    --shadow-dark: rgba(0, 0, 0, 0.3);
    --transition: all 0.3s cubic-bezier(0.4, 0.0, 0.2, 1);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    background: linear-gradient(135deg, var(--bg-primary) 0%, var(--bg-secondary) 100%);
    color: var(--text-primary);
    min-height: 100vh;
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

.app {
    max-width: 600px;
    margin: 0 auto;
    padding: 1rem;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

.header {
    text-align: center;
    margin-bottom: 2rem;
    padding: 2rem 0;
}

.header h1 {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
    background: linear-gradient(135deg, var(--accent-blue), var(--accent-purple));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.header p {
    color: var(--text-secondary);
    font-size: 1.1rem;
    font-weight: 400;
}

.mode-selector {
    display: flex;
    gap: 0.5rem;
    margin-bottom: 2rem;
    background: var(--bg-card);
    padding: 0.5rem;
    border-radius: 1rem;
    border: 1px solid var(--border-color);
}

.mode-btn {
    flex: 1;
    padding: 1rem;
    border: none;
    background: transparent;
    color: var(--text-secondary);
    border-radius: 0.75rem;
    cursor: pointer;
    transition: var(--transition);
    font-size: 0.9rem;
    font-weight: 500;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
}

.mode-btn:hover {
    background: rgba(255, 255, 255, 0.05);
    transform: translateY(-1px);
}

.mode-btn.active {
    background: var(--accent-blue);
    color: white;
    box-shadow: 0 4px 12px rgba(74, 158, 255, 0.3);
}

.progress-bar {
    position: relative;
    background: var(--bg-card);
    height: 0.5rem;
    border-radius: 0.25rem;
    margin-bottom: 2rem;
    overflow: hidden;
    border: 1px solid var(--border-color);
}

.progress-fill {
    height: 100%;
    background: linear-gradient(90deg, var(--accent-green), var(--accent-blue));
    border-radius: 0.25rem;
    transition: width 0.5s ease;
    width: 5%;
}

.progress-text {
    position: absolute;
    top: -1.5rem;
    right: 0;
    font-size: 0.8rem;
    color: var(--text-muted);
    font-weight: 500;
}

.flashcard-container {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 2rem;
    perspective: 1000px;
}

.flashcard {
    width: 100%;
    max-width: 400px;
    height: 300px;
    cursor: pointer;
    transition: transform 0.3s ease;
}

.flashcard:hover {
    transform: scale(1.02);
}

.flashcard-inner {
    position: relative;
    width: 100%;
    height: 100%;
    text-align: center;
    transition: transform 0.6s cubic-bezier(0.4, 0.0, 0.2, 1);
    transform-style: preserve-3d;
}

.flashcard.flipped .flashcard-inner {
    transform: rotateY(180deg);
}

.flashcard-front,
.flashcard-back {
    position: absolute;
    width: 100%;
    height: 100%;
    backface-visibility: hidden;
    border-radius: 1.5rem;
    background: var(--bg-card);
    border: 2px solid var(--border-color);
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 2rem;
    box-shadow: 0 8px 32px var(--shadow-dark);
}

.flashcard-back {
    transform: rotateY(180deg);
    background: linear-gradient(135deg, var(--bg-card) 0%, rgba(74, 158, 255, 0.1) 100%);
}

.card-content {
    width: 100%;
}

.word {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 1rem;
    color: var(--text-primary);
}

.pronunciation {
    font-size: 1.1rem;
    color: var(--text-secondary);
    font-style: italic;
    margin-bottom: 0.5rem;
}

.english-pronunciation {
    font-size: 0.9rem;
    color: #888;
    margin-bottom: 1rem;
    font-weight: 400;
    text-align: center;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.4rem;
}

.english-pronunciation i {
    color: #888;
    font-size: 0.8rem;
}

.translation {
    font-size: 2rem;
    font-weight: 600;
    margin-bottom: 1rem;
    color: var(--accent-blue);
}

.meaning {
    font-size: 1rem;
    color: var(--text-secondary);
    margin-bottom: 1.5rem;
    line-height: 1.5;
}

.gender-info {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
}

.gender {
    color: white;
    padding: 0.5rem 1rem;
    border-radius: 2rem;
    font-weight: 600;
    font-size: 0.9rem;
    transition: var(--transition);
}

/* Default gender styling */
.gender {
    background: var(--accent-orange); /* Default orange */
}

/* Gender-specific colors - higher specificity */
.gender.gender-masculine {
    background: #3b82f6 !important; /* Blue for maskulin */
}

.gender.gender-feminine {
    background: #ec4899 !important; /* Pink for feminin */
}

.gender.gender-neuter {
    background: #10b981 !important; /* Green for neutrum */
}

.gender-reason {
    font-size: 0.8rem;
    color: var(--text-muted);
    font-style: italic;
    max-width: 200px;
    text-align: center;
}

.card-hint {
    position: absolute;
    bottom: 1rem;
    left: 50%;
    transform: translateX(-50%);
    color: var(--text-muted);
    font-size: 0.8rem;
    animation: pulse 2s infinite;
}

/* Hide card hint on the back of the card */
.flashcard-back .card-hint {
    display: none;
}

@keyframes pulse {
    0%, 100% { opacity: 0.6; }
    50% { opacity: 1; }
}

.controls {
    display: flex;
    gap: 1rem;
    justify-content: center;
    margin-bottom: 0.10rem;
}

.control-btn {
    background: var(--bg-card);
    border: 2px solid var(--border-color);
    color: var(--text-primary);
    padding: 1rem 1.5rem;
    border-radius: 1rem;
    cursor: pointer;
    transition: var(--transition);
    font-size: 0.9rem;
    font-weight: 500;
    display: flex;
    align-items: center;
    gap: 0.5rem;
    min-width: 100px;
    justify-content: center;
}

.control-btn:hover {
    background: rgba(255, 255, 255, 0.05);
    transform: translateY(-2px);
    box-shadow: 0 4px 16px var(--shadow-dark);
}

.control-btn:active {
    transform: translateY(0);
}

.flip-btn {
    background: var(--accent-purple);
    border-color: var(--accent-purple);
    color: white;
}

.flip-btn:hover {
    background: rgba(168, 85, 247, 0.8);
    box-shadow: 0 4px 16px rgba(168, 85, 247, 0.3);
}

/* Floating Hamburger Button */
.hamburger-btn {
    position: fixed !important;
    bottom: 9rem !important;
    left: 2rem !important;
    width: 56px !important;
    height: 56px !important;
    background: transparent !important;
    border: 2px solid rgba(255, 255, 255, 0.2) !important;
    border-radius: 50% !important;
    color: rgba(255, 255, 255, 0.8) !important;
    font-size: 1.2rem;
    cursor: pointer;
    box-shadow: none !important;
    backdrop-filter: blur(20px) saturate(180%) !important;
    -webkit-backdrop-filter: blur(20px) saturate(180%) !important;
    transition: background-color 0.3s ease, box-shadow 0.3s ease, border-color 0.3s ease, transform 0.2s ease;
    z-index: 1010 !important;
    display: flex !important;
    align-items: center !important;
    justify-content: center !important;
    transform: translateZ(0) !important;
    min-width: 56px !important;
    min-height: 56px !important;
    max-width: 56px !important;
    max-height: 56px !important;
    flex-shrink: 0 !important;
    flex-grow: 0 !important;
    aspect-ratio: 1/1 !important;
}

/* Prevent any override of button shape */
.hamburger-btn,
.hamburger-btn *,
.hamburger-btn::before,
.hamburger-btn::after {
    border-radius: 50% !important;
    box-sizing: border-box !important;
}

/* Hamburger button when menu is open or on other pages */
.hamburger-btn.menu-open,
.hamburger-btn.transparent {
    background: transparent !important;
    box-shadow: none !important;
    border: 2px solid rgba(255, 255, 255, 0.15) !important;
    color: rgba(255, 255, 255, 0.7);
    border-radius: 50% !important;
    width: 56px !important;
    height: 56px !important;
}

.hamburger-btn.menu-open:hover,
.hamburger-btn.transparent:hover {
    background: rgba(255, 255, 255, 0.1) !important;
    border-color: rgba(255, 255, 255, 0.5);
    transform: scale(1.05);
}

.hamburger-btn:hover {
    background: rgba(255, 255, 255, 0.1) !important;
    border-color: rgba(255, 255, 255, 0.5) !important;
    transform: scale(1.05) translateZ(0);
    box-shadow: 0 6px 20px rgba(0, 0, 0, 0.3) !important;
}

.hamburger-btn:active {
    transform: scale(0.95) translateZ(0);
}

.hamburger-btn:focus {
    outline: none;
    border-radius: 50% !important;
}

/* Side Menu */
.side-menu {
    position: fixed;
    top: 0;
    left: -300px;
    width: 300px;
    height: 100vh;
    background: rgba(26, 26, 26, 0.6);
    backdrop-filter: blur(20px) saturate(180%);
    -webkit-backdrop-filter: blur(20px) saturate(180%);
    border-right: 2px solid rgba(64, 64, 64, 0.4);
    transition: left 0.3s cubic-bezier(0.4, 0.0, 0.2, 1);
    z-index: 1001;
    display: flex;
    flex-direction: column;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.2);
}

.side-menu.open {
    left: 0;
}

.side-menu-header {
    padding: 2rem 1.5rem 1rem;
    border-bottom: 1px solid var(--border-color);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.side-menu-header h2 {
    color: var(--text-primary);
    font-size: 1.5rem;
    font-weight: 600;
    display: flex;
    align-items: center;
    gap: 0.5rem;
    margin: 0;
}

.close-btn {
    background: transparent;
    border: none;
    color: var(--text-secondary);
    font-size: 1.2rem;
    cursor: pointer;
    padding: 0.5rem;
    border-radius: 0.5rem;
    transition: var(--transition);
}

.close-btn:hover {
    background: rgba(255, 255, 255, 0.1);
    color: var(--text-primary);
}

.side-menu-nav {
    flex: 1;
    padding: 1rem 0;
}

.menu-item {
    display: flex;
    align-items: center;
    gap: 1rem;
    padding: 1rem 1.5rem;
    color: var(--text-secondary);
    text-decoration: none;
    transition: var(--transition);
    font-size: 1rem;
    font-weight: 500;
}

.menu-item:hover {
    background: rgba(255, 255, 255, 0.05);
    color: var(--text-primary);
    transform: translateX(5px);
}

.menu-item.active {
    background: rgba(74, 158, 255, 0.1);
    color: var(--accent-blue);
    border-right: 3px solid var(--accent-blue);
}

.menu-item i {
    width: 20px;
    text-align: center;
}

/* Submenu Styles */
.menu-parent {
    position: relative;
}

.menu-toggle {
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.submenu-arrow {
    transition: transform 0.3s ease;
    font-size: 0.8em;
    margin-left: auto;
}

.menu-parent.open .submenu-arrow {
    transform: rotate(180deg);
}

.submenu {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease;
    background: rgba(0, 0, 0, 0.2);
    border-radius: 8px;
    margin: 4px 0;
}

.menu-parent.open .submenu {
    max-height: 200px;
}

.submenu-item {
    padding-left: 3rem !important;
    font-size: 0.9em;
    border-left: 2px solid rgba(75, 85, 99, 0.3);
    margin-left: 1rem;
}

/* Menu Overlay */
.menu-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    background: rgba(0, 0, 0, 0.5);
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s ease;
    z-index: 999;
}

.menu-overlay.active {
    opacity: 1;
    visibility: visible;
}

/* Pages */
.page {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    background: var(--bg-primary);
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s ease;
    z-index: 998;
    overflow-y: auto;
}

.page.active {
    opacity: 1;
    visibility: visible;
}

.page-content {
    max-width: 600px;
    margin: 0 auto;
    padding: 2rem 1rem;
    min-height: 100vh;
    position: relative;
}

.back-btn {
    background: var(--bg-card);
    border: 2px solid var(--border-color);
    color: var(--text-primary);
    padding: 0.75rem 1rem;
    border-radius: 0.75rem;
    cursor: pointer;
    transition: var(--transition);
    font-size: 0.9rem;
    font-weight: 500;
    display: flex;
    align-items: center;
    gap: 0.5rem;
    margin-bottom: 1.5rem;
    width: fit-content;
}

.back-btn:hover {
    background: rgba(255, 255, 255, 0.05);
    transform: translateX(-2px);
    box-shadow: 0 4px 16px var(--shadow-dark);
}

.back-btn i {
    font-size: 0.8rem;
}

.page-content h2 {
    color: var(--text-primary);
    font-size: 2rem;
    margin-bottom: 2rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

/* Instructions Page Styling */
.instruction-section {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 1rem;
    padding: 1.5rem;
    margin-bottom: 1.5rem;
}

.instruction-section h3 {
    color: var(--accent-blue);
    margin-bottom: 1rem;
    font-size: 1.1rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.instruction-section ul {
    list-style: none;
    margin: 0;
    padding: 0;
}

.instruction-section li {
    margin-bottom: 0.75rem;
    color: var(--text-secondary);
    font-size: 0.95rem;
    line-height: 1.5;
}

.instruction-section strong {
    color: var(--text-primary);
}

.shortcuts-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    gap: 1rem;
    margin-top: 1rem;
}

.shortcut {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 0.75rem;
    background: rgba(255, 255, 255, 0.03);
    border-radius: 0.5rem;
    border: 1px solid var(--border-color);
}

.shortcut kbd {
    background: var(--accent-blue);
    color: white;
    padding: 0.25rem 0.5rem;
    border-radius: 0.25rem;
    font-size: 0.75rem;
    font-weight: 600;
    min-width: 24px;
    text-align: center;
}

.shortcut span {
    color: var(--text-secondary);
    font-size: 0.85rem;
}

/* About Page Styling */
.about-section p {
    color: var(--text-secondary);
    line-height: 1.6;
    margin-bottom: 1.5rem;
}

.about-section h3 {
    color: var(--accent-blue);
    margin: 2rem 0 1rem;
    font-size: 1.2rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.about-section ul {
    list-style: none;
    padding: 0;
}

.about-section li {
    color: var(--text-secondary);
    margin-bottom: 0.5rem;
    padding-left: 1.5rem;
    position: relative;
}

.about-section li:before {
    content: "✓";
    position: absolute;
    left: 0;
    color: var(--accent-green);
    font-weight: bold;
}

.credits {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 1rem;
    padding: 1.5rem;
    margin-top: 2rem;
    text-align: center;
}

.credits p {
    margin-bottom: 0.5rem;
}

.credits p:last-child {
    margin-bottom: 0;
}

/* Legend Page Styling */
.legend-section {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 1rem;
    padding: 1.5rem;
    margin-bottom: 1.5rem;
}

.legend-section h3 {
    color: var(--accent-blue);
    margin-bottom: 1rem;
    font-size: 1.2rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.legend-section p {
    color: var(--text-secondary);
    margin-bottom: 1rem;
    line-height: 1.5;
}

.gender-legend {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.gender-item {
    display: flex;
    align-items: center;
    gap: 1rem;
    padding: 1rem;
    background: rgba(255, 255, 255, 0.03);
    border-radius: 0.75rem;
    border: 1px solid var(--border-color);
}

.gender-explanation {
    display: flex;
    flex-direction: column;
    gap: 0.25rem;
}

.gender-explanation strong {
    color: var(--text-primary);
    font-size: 1rem;
}

.gender-explanation span {
    color: var(--text-muted);
    font-size: 0.85rem;
    font-style: italic;
}

.abbr-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1rem;
}

.abbr-item {
    display: flex;
    align-items: center;
    gap: 1rem;
    padding: 0.75rem;
    background: rgba(255, 255, 255, 0.03);
    border-radius: 0.5rem;
    border: 1px solid var(--border-color);
}

.abbr-item strong {
    color: var(--accent-blue);
    font-size: 1rem;
    min-width: 40px;
}

.abbr-item span {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.rules-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 1rem;
}

.rule-card {
    background: rgba(255, 255, 255, 0.03);
    border: 1px solid var(--border-color);
    border-radius: 0.75rem;
    padding: 1rem;
}

.rule-card h4 {
    color: var(--text-primary);
    margin-bottom: 0.75rem;
    font-size: 1rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.rule-card h4:before {
    content: "•";
    color: var(--accent-green);
    font-size: 1.2rem;
}

.rule-card ul {
    list-style: none;
    padding: 0;
    margin: 0;
}

.rule-card li {
    color: var(--text-secondary);
    margin-bottom: 0.5rem;
    padding-left: 1rem;
    position: relative;
    font-size: 0.9rem;
}

.rule-card li:before {
    content: "→";
    position: absolute;
    left: 0;
    color: var(--accent-blue);
    font-size: 0.8rem;
}

.pattern-list {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.pattern-item {
    padding: 1rem;
    background: rgba(255, 255, 255, 0.03);
    border-radius: 0.5rem;
    border: 1px solid var(--border-color);
    color: var(--text-secondary);
    font-size: 0.9rem;
    line-height: 1.5;
}

.pattern-item strong {
    color: var(--accent-green);
}

/* Animations */
.slide-in-left {
    animation: slideInLeft 0.5s ease-out;
}

.slide-in-right {
    animation: slideInRight 0.5s ease-out;
}

/* Gender Pages Styling */
.gender-page .page-content {
    max-width: 800px;
}

.gender-intro {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 1rem;
    padding: 1.5rem;
    margin-bottom: 2rem;
}

.gender-intro p {
    margin: 0;
    color: var(--text-secondary);
    line-height: 1.6;
}

.rule-section {
    margin-bottom: 2.5rem;
}

.rule-section h3 {
    color: var(--accent-blue);
    margin-bottom: 1.5rem;
    font-size: 1.3rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
    border-bottom: 2px solid var(--border-color);
    padding-bottom: 0.5rem;
}

.rule-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 1.5rem;
    margin-bottom: 1.5rem;
}

.rule-item {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 0.75rem;
    padding: 1.25rem;
}

.rule-item h4 {
    color: var(--text-primary);
    margin-bottom: 1rem;
    font-size: 1.1rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.rule-item ul {
    list-style: none;
    margin: 0;
    padding: 0;
}

.rule-item li {
    color: var(--text-secondary);
    margin-bottom: 0.5rem;
    padding-left: 1rem;
    position: relative;
}

.rule-item li:before {
    content: "•";
    color: var(--accent-blue);
    position: absolute;
    left: 0;
    font-weight: bold;
}

.ending-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 1rem;
    margin-bottom: 1.5rem;
}

.ending-item {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 0.5rem;
    padding: 1rem;
    text-align: center;
}

.ending-item h4 {
    color: var(--accent-blue);
    margin-bottom: 0.5rem;
    font-size: 1.1rem;
    font-family: 'Courier New', monospace;
}

.ending-item p {
    color: var(--text-secondary);
    margin: 0;
    font-size: 0.9rem;
    line-height: 1.4;
}

.exception-section {
    background: rgba(239, 68, 68, 0.1);
    border: 1px solid rgba(239, 68, 68, 0.3);
    border-radius: 1rem;
    padding: 1.5rem;
    margin-bottom: 2rem;
}

.exception-section h3 {
    color: #ef4444;
    border-bottom-color: rgba(239, 68, 68, 0.3);
}

.exception-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 1rem;
}

.exception-item {
    background: rgba(0, 0, 0, 0.2);
    border: 1px solid rgba(239, 68, 68, 0.2);
    border-radius: 0.5rem;
    padding: 1rem;
}

.exception-item h4 {
    color: #ef4444;
    margin-bottom: 0.75rem;
    font-size: 1rem;
}

.exception-item ul {
    list-style: none;
    margin: 0;
    padding: 0;
}

.exception-item li {
    color: var(--text-secondary);
    margin-bottom: 0.4rem;
    padding-left: 1rem;
    position: relative;
    font-size: 0.9rem;
}

.exception-item li:before {
    content: "⚠";
    color: #ef4444;
    position: absolute;
    left: 0;
    font-size: 0.8rem;
}

.tip-section {
    background: rgba(16, 185, 129, 0.1);
    border: 1px solid rgba(16, 185, 129, 0.3);
    border-radius: 1rem;
    padding: 1.5rem;
    margin-bottom: 2rem;
}

.tip-section h3 {
    color: #10b981;
    border-bottom-color: rgba(16, 185, 129, 0.3);
}

.tip-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 1rem;
}

.tip-item {
    background: rgba(0, 0, 0, 0.2);
    border: 1px solid rgba(16, 185, 129, 0.2);
    border-radius: 0.5rem;
    padding: 1rem;
}

.tip-item h4 {
    color: #10b981;
    margin-bottom: 0.75rem;
    font-size: 1rem;
}

.tip-item p {
    color: var(--text-secondary);
    margin: 0;
    font-size: 0.9rem;
    line-height: 1.5;
}

/* Copyright Footer - Visible on all screens */
.copyright-footer {
    text-align: center;
    padding: 0.5rem 1rem;
    margin-top: 0.2rem;
    color: rgba(255, 255, 255, 0.4);
    font-size: 0.7rem;
    font-weight: 300;
    letter-spacing: 0.5px;
}

/* Mobile copyright styling */
@media (max-width: 480px) {
    .copyright-footer {
        font-size: 0.65rem;
        padding: 0.5rem 0.4rem;
        margin-top: 0.4rem;
    }
}

@keyframes slideInLeft {
    from {
        opacity: 0;
        transform: translateX(-100px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

@keyframes slideInRight {
    from {
        opacity: 0;
        transform: translateX(100px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

/* Mobile Responsive */
@media (max-width: 768px) {
    .app {
        padding: 0.5rem;
    }
    
    .header h1 {
        font-size: 2rem;
    }
    
    .flashcard {
        height: 280px;
    }
    
    .word, .translation {
        font-size: 2rem;
    }
    
    .controls {
        gap: 0.5rem;
    }
    
    .control-btn {
        padding: 0.8rem 1rem;
        font-size: 0.8rem;
        min-width: 80px;
    }
    
    .mode-btn {
        padding: 0.8rem;
        font-size: 0.8rem;
    }
    
    /* Mobile hamburger button */
    .hamburger-btn {
        bottom: 6rem !important;
        left: 1.5rem !important;
        width: 50px;
        height: 50px;
        font-size: 1.1rem;
    }
    
    /* Mobile side menu */
    .side-menu {
        width: 280px;
        left: -280px;
    }
    
    .side-menu-header {
        padding: 1.5rem 1rem 1rem;
    }
    
    .side-menu-header h2 {
        font-size: 1.3rem;
    }
    
    .menu-item {
        padding: 0.75rem 1rem;
        font-size: 0.9rem;
    }
    
    .shortcuts-grid {
        grid-template-columns: 1fr;
    }
    
    /* Mobile legend page */
    .rules-grid {
        grid-template-columns: 1fr;
    }
    
    .abbr-grid {
        grid-template-columns: 1fr;
    }
    
    .gender-item {
        flex-direction: column;
        align-items: flex-start;
        gap: 0.75rem;
    }
}

@media (max-width: 480px) {
    .flashcard {
        height: 250px;
    }
    
    .card-content {
        padding: 1rem;
    }
    
    .word, .translation {
        font-size: 1.8rem;
    }
    
    .controls {
        flex-wrap: wrap;
    }
    
    .control-btn {
        flex: 1;
        min-width: 100px;
    }
}